Signal discriminating device for VTR having expanded dynamic range
US5075803A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Apr 6, 1989 |
| Grant date | Dec 24, 1991 |
| Priority date | — |
| Expiry date | Apr 6, 2009 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N9/833
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A magnetic recording and reproducing apparatus having a first recording mode and a second recording mode in which a luminance signal of a video signal is converted into FM luminance signal related to a first carrier frequency and to a second carrier frequency so as to be recorded on a magnetic tape includes a discriminating device or discriminating a recording mode in which an FM luminance signal reproduced from a magnetic tape so as to be supplied to a playback circuit has been recorded. The signal discriminating device includes an automatic gain control (AGC) circuit for absorbing a dispersion of the reproduced signal, a discrimiating circuit having a first band-pass filter and a second band-pass filter for processing an output from the AGC circuit so as to discriminate the first and second modes, a detecting circuut to which the reproduced signal is supplied in a parallel fashion with respect to the AGC circuit such that an amplitude of the signal is detected and is then compared with a predetermined value so as to obtain noise information, and a latch circuit for latching an output from the discriminating circuit such that in response to the noise information from the detecting…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.